The present invention relates to a drive control device for a hybrid compressor that constitutes part of a refrigerating cycle of an air-conditioning system installed in a hybrid car, an idle-stop car, an electric car or the like and includes two drive sources, i.e., an engine for traveling and a motor.
In an operation control device for a car compressor disclosed in Japanese Unexamined Patent Publication No. H 9-324668, a rotor provided for power generation can be switched to function as an electric motor by an inverter. The output shaft of the rotor is linked to a drive shaft of an air-conditioning compressor and to a crankshaft of an internal combustion engine via belts, a compressor clutch is provided at the drive shaft of the compressor and a crank clutch is provided at the crankshaft so that the fuel supply is cut off to stop the internal combustion engine, the crank clutch is disengaged and the compressor clutch is engaged to drive the compressor with the rotor by electrically operating the rotor in the event that the vehicle stops due to a red signal or the like during operation of the air-conditioning system.
However, if an electrical or mechanical failure occurs in the motor in the vehicle compressor operation control device described above, a traveling engine stop suspends the compressor operation, which poses a problem in that the air-conditioning state deteriorates. In addition, there is a concern that a mechanical failure in the motor adversely affects the rotational load of the traveling engine.
Accordingly an object of the present invention is to provide a drive control device for a hybrid compressor, that is capable of taking appropriate measures in the event of a motor failure in correspondence to the type of motor failure.
In order to achieve the object described above, the present invention provides a hybrid compressor that constitutes part of a refrigerating cycle, includes an engine for traveling and a motor to function as drive sources and is driven by the motor if the traveling engine stops, comprising a motor drive means that supplies power to the motor if a traveling engine stop is indicated and the hybrid compressor operation is to continue, an electrical abnormality judgment means that makes a decision as to whether or not an abnormality has occurred in the power supply to the motor by the motor drive means and a compressor operation continuation means that secures a drive source for the hybrid compressor by allowing the operation of the traveling engine to continue if the electrical abnormality judgment means decides that a power supply abnormality has occurred. In addition, it is desirable that the electrical abnormality judgment means monitor the level of the electrical current flowing in response to a voltage application to the motor and decide that a power supply abnormality has occurred if the value of the electrical current is either extremely low or extremely high.
This structure allows the air-conditioning operation to be performed continuously as the compressor operation continuation means disallows a traveling engine stop to secure a drive source for the hybrid compressor if the electrical abnormality judgment means decides that an abnormality has occurred in the power supply to the motor.
Alternatively, a hybrid compressor according to the present invention that constitutes part of a refrigerating cycle, includes an engine for traveling and a motor to function as drive sources and is driven by the motor if the traveling engine stops, may comprise a motor drive means that supplies power to the motor if a traveling engine stop is indicated and the compressor operation is to continue, a mechanical abnormality judgment means that makes a decision as to whether or not an abnormality has occurred with regard to the motor drive state after the power is supplied to the motor by the motor drive means and an engine protection means that protects the traveling engine by cutting off the connection between the traveling engine and the hybrid compressor if the mechanical abnormality judgment means decides that an abnormality has occurred in the motor drive state. It is desirable that the mechanical abnormality judgment means monitor the rotation rate of the motor following the power supply by the motor drive means and decide that a mechanical abnormality has occurred if the motor rotation rate does not rise to a level equal to or higher than a predetermined rotation rate.
In the structure described above, the connection between the hybrid compressor and the traveling engine is cut off if the mechanical abnormality judgment means decides that the motor drive state is abnormal, thereby protecting the traveling engine from the mechanical abnormality manifesting in the hybrid compressor.
As a further alternative, a hybrid according to the present invention that constitutes part of a refrigerating cycle, includes an engine for traveling and a motor to function as drive sources and is driven by the motor if the traveling engine stops, may comprise a motor drive means that supplies power to the motor if a traveling engine stop is indicated and the hybrid compressor operation is to continue, an electrical abnormality judgment means that makes a decision as to whether or not an abnormality has occurred in the power supply to the motor by the motor drive means, a compressor operation continuation means that secures a drive source for the hybrid compressor by allowing the operation of the traveling engine to continue if the electrical abnormality judgment means decides that a power supply abnormality has occurred, a motor drive means that supplies power to the motor if a traveling engine stop is indicated and the compressor operation is to continue, a mechanical abnormality judgment means that makes a decision as to whether or not an abnormality has occurred with regard to the motor drive state after the power is supplied to the motor by the motor drive means and an engine protection means that protects the traveling engine by cutting off the connection between the traveling engine and the hybrid compressor if the mechanical abnormality judgment means decides that an abnormality has occurred in the motor drive state.
This structure allows the air-conditioning operation to be performed continuously as the compressor operation continuation means disallows a traveling engine stop to secure a drive source for the hybrid compressor if the electrical abnormality judgment means decides that an abnormality has occurred in the power supply to the motor and, protects the traveling engine from the mechanical abnormality manifesting in the hybrid compressor by cutting off the connection between the hybrid compressor and the traveling engine is cut off if the mechanical abnormality judgment means decides that the motor drive state is abnormal.
In addition, it is desirable that the hybrid compressor be provided with a power supply abnormality indicator means that indicates a power supply abnormality if the electrical abnormality judgment means decides that a power supply abnormality has occurred. It is also desirable that the hybrid compressor be provided with a drive abnormality indicator means that indicates a drive state abnormality if the mechanical abnormality judgment means decides that an abnormality has occurred in the motor drive state. These means warn the driver of a motor abnormality and also indicate the type of abnormality as well.